By Lisa Owens Viani

Birds’ eggs don’t lie. Just as thinning eggshells once revealed how DDT was affecting peregrines and pelicans, the eggs themselves are now telling scientists how long-lived some contaminants are in the Estuary and where they are the most problematic. A report just published by the Regional Monitoring Program for Water Quality in San Francisco Bay (RMP) summarizes contaminant concentrations in eggs collected between 2002 and 2012 from two fish-eating species high in the Estuary food chain, double-crested cormorants and Foster’s terns. Double-crested cormorants are considered a sentinel species for open water; Forster’s terns for shallow-water habitats on the Estuary’s margins, including wetlands and managed ponds.

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An Eggfull of Estuary

By Lisa Owens Viani

Birds’ eggs don’t lie. Just as thinning eggshells once revealed how DDT was affecting peregrines and pelicans, the eggs themselves are now telling scientists how long-lived some contaminants are in the Estuary and where they are the most problematic. A report just published by the Regional Monitoring Program for Water Quality in San Francisco Bay (RMP) summarizes contaminant concentrations in eggs collected between 2002 and 2012 from two fish-eating species high in the Estuary food chain, double-crested cormorants and Foster’s terns. Double-crested cormorants are considered a sentinel species for open water; Forster’s terns for shallow-water habitats on the Estuary’s margins, including wetlands and managed ponds.

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About the author

Lisa Owens Viani is a freelance writer and editor specializing in environmental, science, land use, and design topics. She writes for several national magazines including Landscape Architecture Magazine, ICON and Architecture, and has written for Estuary for many years. She is the co-founder of the nonprofit Raptors Are The Solution, www.raptorsarethesolution.org, which educates people about the role of birds of prey in the ecosystem and how rodenticides in the food web are affecting them.

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